Method of forming hollow concrete bodies



June29, 1965 J. E. BANKS 3,192,292

METHOD OF FORMING HOLLOW CONCRETE BODIES Filed Dec. '7, 1961 4 Sheets-Sheet 1 YY' L l L Li 6L6 INVENTOR.

Jdsf H 5, 5mm? @M/QHM Jun 29, 6 J. E. BANKS 3,192,292

METHOD OF FORMING HOLLOW CONCRETE BODIES Filed Dec. 7, 1961 4 Sheets-Sheet 2 Tic 5. 7 7 7/ y;

INV EN TOR. JOSEPH E BAN/rs BY 14 TTOK/VE) June 29, 1965 J. E. BANKS METHOD OF FORMING HOLLOW CONCRETE BODIES 4 Sheets-Sheet 5 Filed D60. 7. 1961 0 5 w w 1 1 m; 9;, I 123 "I llllllllll INVENTOR. Jose h A". 54mm" AVAYAV A W AV AV/A fw June 29, 1965 J. E. BANKS METHOD OF FORMING HOLLOW CONCRETE BODIES Filed Dec. 7. 1961 4 Sheets-Sheet 4 R H. mm W .m m5 0 T m w E a 4 m m E l WW W w 1 l.. .11 a l T v C 3 m w H W. m N, m w 7 E w C w 3 w H x United States Patent METHGD 0F FORMENG HOLLOW CONCRETE EGDIE Joseph E. Banks, Miami, Fla. (1411 Marion Ave., Tallahassee, Fla.) Filed Dec. 7, 1961, Ser. No. 157,734 13 Claims. (Cl. 264-32) This invention pertains to methods of forming hollow concrete bodies such as the production of hollow concrete pipes or hollow concrete pilings in the ground and the production of concrete blocks or pipe sections as articles of manufacture.

It is usual to insert in an oil well a tubular metal casing, and it is frequently desirable to fill the space between the casing and the hole with cement at one or more localities to shut off the production of salt water or other extraneous matter and'to'hold back mud and sand, when it is desired to produce oil. When the casing is set in position in the hole, it is usually by means of a high pressure pump to introduce inside the casing the cement in a soft, wet state, commonly referred to as cement grout, under pressure sufficient so that the cement is forced down through the casing, out through the bottom of the casing, and up along the walls of the casing so that it completely fills the space between the casing and the borehole of the well in any section where it is desired to shut olf extraneous matter, such as salt water, for example, that interferes with the oil production.

After the wells are in service and oil has been produced to the extent that the well has run dry, the casing in the ground may be abandoned, but so far as possible, it is desirable to recover it for use in another location. It has been found practically impossible to recover casing when it is set in solid, fully hardened cement which adheres not only to the inner walls of the borehole but also to the outer-surface of the casing.

By the use of this invention it is possible to avoid the freezing of thecement on the outer surface of the casing, although the space which is left between the casing and the cement is very small and will not in any Way interfere with the operation of the well. Nevertheless, with the usualrnechanism for pulling the casing, it may be withdrawn and is ready for further use, leaving a well hole cased, at least in part, with concrete instead of with steel.

Another application of the invention is found in the production of hollow concrete pipes in the ground, to

create a concrete-cased well hole or a hollow concrete pile. Hollow concrete piles, in the shape of reinforcedconorete cylinders which are prefabricated before being driven, are well known. According to my invention'any of the well known methods of drilling or punching a hole in the ground can be used, such asthose described in Robert A.- Cummings United Stateslatent No. 822,588,

issued June 5, 1906. Then a smaller-diameter, substantially-cylindrical core, which may besolid or hollow, is centered in the hole and concrete poured between the core and the walls of the hole in the ground, and the core is rotated as hereinafter described in relation to oil well casing. The cement grout or wet concrete will not adhere to' the outside of the metal core, the bottom end of which is closed against entry of .wet cementin this application,

and when, the concrete is set, the core may be withdrawn,

leaving the hollow concrete pipe or pilev in the ground.

, .A further application of this invention is to the production of hollow concrete pipe and also the formation of concrete blocks with a hollow, approximately cylindrical center in which a core and a mould are employed and one or. bothof which are adapted to be rotated while the, wet concrete is introduced in the space between the two and ,while it sets. I

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The foregoing objectives are obtained in accordance with this invention by providing suitable means for imparting an extremely slow movement to the casing in the oil well and likewise a very slow movement to the metal core in the hollow concrete pipe or pile, and to the mould and core, or only to the core, when used to make concrete blocks or pipe sections, during the entire period from the time the wet concrete is poured until it is fully set. The movement which I now believe to be preferable is a very slow rotary movement, such as for example a rotation at the rate of one revolution per minute or less, a rate which is sufficiently low to keep the cement from forming a bond with the outside of the central casing or core, but not sufliciently high to keep the concrete from solidifying in the usual manner.

The speed of circumferential movement of the outer surface of the core or casing should be very slow, and the movement in rotational turns per minute will vary with the diameter of the core or casing. The action of the smooth moving'surface of the core or casing against the cement or concrete as it hardens is believed to be comparable to a tr-oweling effect which results in a smooth inner surface of the cylindrical hole and makes possible the ready removal of the core or casing after the cement or concrete is fully set.

The best embodiments of the invention now known to me are fully described in the following'specification and illustrated in the drawings, to which reference may now be had:

FIG. 1 is a partially sectional elevation of an oil well casing set in the borehole and provided with mechanism for gripping the casing and for slowly rotating the casing while the cement grout is introduced and hardened.

FIG. 2 is a plan view of the structure shown in FIG. 1.

FIG. 3 is an enlarged partially sectional plan view taken on the line 3-3 of FIG. 1.

FIG. 4 is an enlarged sectional elevation taken on the line 4-4 of FIG. 1.

FIG. 5 is a View corresponding to FIG. 1, which shows a substantially cylindrical hole in the earth with a tapered core centrally mounted therein and a driving mechanism adapted to slowly rotate the core as the wet concrete is poured down the hole around the core.

FIG. 6 is a plan view partially broken away to show the large drive gear which is attached to the top of the core.

FIG. 7 is a sectional elevation of a structure composed of a cylindrical mould and a substantially cylindrical core, both of which are rota-ted preferably in opposite directions, while the wet concrete is introduced between the two, and continuously until the concrete has completely set.

FIG. 8 is a sectional plan View on the line $8 of FIG; 7. I

"FIG. 9 corresponds to FIG. 7, but in this arrangement the mould is stationary and is made in connecting halves, whereas the core only is slowly rotated while the wet concrete is introduced between the core and the stationary mould.

FIG. 9.

FIG. 11 is a detailed view of an oscillation mechanism which may be introduced between the driving motor and the gear connections in any of the preceding figures.

FIG. 12 is a partially sectional elevation which corresponds generally to FIG. 1 of another embodiment of my invention, in which the casing is given an up-anddown or vibratory motion instead of a rotary motion.

FIG. 13 is a partially sectional plan view taken on the line 13-43 of FIG. 12.

FIG. 14 is a partially sectional bottom view taken on the line 1414 of FIG. 12.

FIG. 10 is a plan view taken on the line 1010 of v FIG. .15 is a view corresponding to FIG. 1 and FIG. 12 of another embodiment of my invention, in which the casing has imparted to it both a slow rotary motion, as in FIG. 1, and a slow longitudinal vibratory or up-anddown motion, as shown in FIG. 12.

FIG. 16 is a partially sectional view taken on the line 16.16.of FIG. 15.

Referring particularly to FIGS. 1 to 4, inclusive, 11 represents a borehole in the earth, such as for example an oil well, and 11 is a casing which is of ordinary construction, although preferably it has no external collars but has a smooth exterior surface. The casing is held in the jaws or wedge blocks 12 which are set in the tapered opening 13 of a rotary table 15.

' The rotary table is set in a cylindrical recess 16 in a foundation block 17. The cylindrical recess 16 in the block 17 has a shallow countersunk cylindrical opening 2%, and the cylindrical recess 16 extends close to the bottom so as to leave a hollow, disc-shaped supporting ledge 21.

A plurality of rollers are mounted on vertical axes 26 and are of a size to support the sidewall 27 of the rotary table, as clearly shown in FIG. 3.

The rotary table is supported from the base 17 at the bottom by rollers 30 mounted in a roller race 31 which forms a circular groove in the disc-shaped supporting ledge 21. The rollers 31) are mounted as shown in FIG. I

4 and carry the entire weight of the rotary table and of the casing which it supports.

Attached to the top of the rotary table by any suitable means such'as bolts 41), is a large gear wheel 41 which is driven by a pinion 42 mounted on a shaft 43 which is supported from the base 17 by a bearing bracket 45. The bearing bracket is fastened to the base by bolt 46 or other suitable means. Below the bearing on the shaft 43 is .mounted a bevel gear wheel 47. A motor 50 is mounted on the base and adapted to drive bevel gear 51 which meshes with the bevel gear 47.

The arrangement is suchthat whenthe motor is op-- erated at normal speed,,there is a great'reduction of speed from the motor shaft to the gear wheel 42 which hole will restrain the cement against rotating, and although the final space left between the casing and the cement is extremely small, there is enough space left when the concrete is finally set so that the casing may be readily withdrawn when it is desired to recover the casing.

The same principle which is described above is also incorporated in the structure of FIGS. 5 and 6 for the creation of a hollow concrete pipe or pile in the ground, except that in such case the grout or wet concrete would be poured between the wall 89 of the borehole and the outside of the central core 83, instead of injected through the center of the casing, and the bottom of the central core would be closed by a centering plug 81. Thereafter the central core would be rotated very slowly until the concrete had set and then pulled out for reuse, as hereinbefore described.

The core 83 is. inserted centrally of the borehole 80, is usually tapered slightly as indicated in the drawings,

and has a concave conical recess 84 at its lower end i which cooperates with the. cone 81 and centers the core. The core is smaller than the interior of the borehole 80 and leaves a space 86 which indicates the thickness of the walls of'the hollow concrete pipe or pile that is to be produced.

If a hollow concrete pile having relatively thin walls is desired, the core 83 will more largely fill the space and if, on the other hand, the hollow concrete pile is to have thick walls, as shown in FIG. 5, the core is prois designed to operate very slowly and may, for example,

be rotated at one revolution'per minute, or even less.

The wedge blocks 12, as shown, are three in number and are designated 12a,- 12b and 12c in FIG. 2. The blocks 12b and 120 are hinge-connected by cooperating lugs and hinge pins 61 with the wedge blocks 12a. Lifting handles 63, 64 are hinge-connected to the ends of 12b and 12c, and lifting handle 65 is hinge-connected to the wedge block 12a. These lifting handles are ordinarily heavy in construction and terminate in loops, such as loops 7!), and are thus adapted to receive hooks from the usual hoists (not shown).

If the casing is set in a borehole, as shown in FIG. 1, and it is desired to cement the casing, it isusual to pump cement grout under high pressure into the open end 71 of the casing at the top so that it will be forced downwardly through the casing and out at the bottom and upwardly into the annular space 72 between the casing and the wallsrof the borehole.

When this operation is proceeding in accordance with my invention, the motor 'SGis operated and the rotary table is turned by the gear 41 at very slow speed so that the casing is rotated at the desired peripheral speedduring the entire time that the cement grout is introduced,

forced out of the casing and up around the casing in the spacevbetween the walls of the borehole and the casing. Furthermore, the rotation is continued during the entire operation until the cement is completely setand forms a solid mass. The rotational speed may be varied between the time the cement is introduced and the longer interval when the cement is setting, to obtain the best troweling action.

By reason of the fact that the casing is turned very slowly, the cement will not adhere to the outer smooth wall of the casing, while friction with the rough boreportionately smaller.

A gear wheel 87 is attached to the core 83 at the top, and the core has a shaft extension 89 which is mounted in the bearing 90 supported at the top of the core by arms 91 which extend, as shown in FIG. 6, to a stationary block or base 92 to which the arms are secured to the reduction gear structure shown in FIGS. 1 and 2 and is for the purpose of slowly rotating the core 83 while the cement grout or wet concrete is introduced into the space 86 between the core and the borehole 80. The slow movement of the core continues during the entire operation as the space 86 is filled with cement grout.

or wet concrete and thereafteruntil the concrete is completely set.. a

By reason of the fact that the; core is slowly moving during this. entireperiod, itcan be withdrawn after the cement is set without difliculty and again used in the manufacture of another hollow concrete pipe or pile in the same fashion.

The same principle is applied in a further embodiment of this invention, to the manufacture of hollow concrete pipe, as illustrated; in FIGSQ: 7 and 8, to which special reference will now be had:

A hollow cylindrical mould is rotatably mounted on base 111 having an annular projection 112. A hollow cylinder 110 fits over the annular projection 112 at the bottom and preferably has rollers 113 which contact the smooth upper surface 114 of the base 111. In the center of the base 111 is a shallowcylindricalhole 115 in which the-bottom of a core'116 is inserted. Rollers 117 are mounted on the base v111 in a roller race 118 so that the core may be readily rotated.

At the top of the mould 110 is a gear wheel 120 which meshes with pinion 121 on vertical shaft 122. A hollow disc 125 is mountedon any'suitable structure 126 and constitutes anvupper base for supporting driving motor 127. Brackets 128, 129-arewelded or bolted to the upper base 125 or are otherwise firmly attached thereto.

A bracket 128. attached to the upper-base 125 has a bearing 130, which supports the outer end of the motor drive shaft 131. The bracket also supports a vertical shaft 135 with a bevel gear 136 above the bracket and a pinion 137 below the bracket. Attached to the motor shaft 131 are two bevel gears 140, 141. A gear wheel 145 is firmly attached to the core 116 at the top and meshes with the pinion 137 and is driven thereby. The gear wheel 120, which is attached to the core 110 near the top, meshes with pinion 121 which is driven from bevel gear 141 by bevel gear 148 attached to the shaft 122 at the top.

Guide shoes 150, only one of which is shown in FIG. 7, support the mould 110 near the top and hold it in an upright position. Likewise shoes 155, only one of which is shown, may be utilized to center the core 116 at the top.

When the motor 127 is operated, the gear drives are so arranged, as clearly indicated, that the core 116 will be driven, for example, in a counterclockwise direction, whereas the gear 120' mounted on the mould 110 will at the same time be rotated in a clockwise direction.

Very low speeds of the moving parts prevent the cement from adhering to an ordinary steel surface.

The core 116 is preferably hollow, as shown in FIG. 8.

A reinforcing structure or cage 156, consisting of a helix 157 made up of heavy rough wire or a plurality of hoops spaced and attached to reinforcing rods 158, is preferably introduced in the space between the mould 110 and the core 116. This has the advantage not only of reinforcing the concrete pipe section being formed, but also of preventing the concrete mix from moving with either the mould or the core. Referring to FIGS. 9 and 10, which correspond to FIGS. 7 and 8, and show a corresponding structure: the motor 160 has a short drive shaft 161 to which a bevel gear 162 is attached. This gear is mounted on a shaft 163 which also carries a pinion 164. A gear wheel 165, which corresponds to gear wheel 145, is attached to the core 166 which corresponds to core 116 and is similarly mounted in its base 167. In this structure, however, the mould 170, as clearly shown in FIG. 10, is made up in halves 170a and 170b, which are hinge-connected at 171 by lugs 172 which are fastened together by any suitable means such as bolts 173 when the mould is closed.

In this structure when the cement grout is introduced between the mould and the core, the mould is stationary, but the core is rotated very slowly.

When the cement has completely hardened, the core is readily removed because the rotation has prevented the concrete from sticking to it and the mould 170 is opened 'by disengaging the bolt 173 and swinging the halves 170a and 1701) open.

The stationary mould is not necessarily cylindrical and, in fact, may be square or multisided, depending upon the desired formation of the block or pipe section being produced.

Referring to FIG. 11, an oscillator mechanism 175 is here shown but is not described in detail, since it per se forms no part of my invention and may be of any well known construction.

The oscillator mechanism may be introduced between the motor and the gear shaft of any of the preceding figures. When it is so introduced and the motor is operated, the parts heretofore described as rotating will be given an oscillatory movement in a rotary direction, but the movement must be very slow, as already described, when the parts are rotated.

Having special reference to FIGS. 12, 13 and 14, the casing 180 is supported in the wedge blocks or jaws 181 and the rotary table 182, which has guide rollers 183 mounted on supporting brackets 184 but in this case is held against rotation by arm 185 which is bolted to the rotary table 182 and is fastened to one of the arms 184, as shown in FIG. 12.

The base block 184 has an annular horizontal supporting surface 186, and a roller cage 187 is interposed between the annular surface in the base and the bottom surface of the rotary table. The cage 187 comprises a gear wheel 188, as shown in FIG. 13, having a plurality of circumferentially arranged openings 190, in each of which a heavy roller 191 is rotatably mounted on pins 192.

The bottom surface of the rotary table 182, which is directly above the annular surface 186, is formed into a series of segmental ring-shaped cams.

The gear wheel 188 is driven by a pinion 193 on shaft 194, which carries a bevel gear 195 meshing with a bevel pinion 196. This pinion is driven by motor shaft 187 to which it is attached. Motor 198 may be an electric motor or any other suitable prime mover.

The structure of FIGS. 12, 13 and 14 is such that when the motor 198 is operated, the gear Wheel 188 is driven to rotate slowly around the axis of the casing 180. Since the table 182 is held against rotation, the roller cage 187, as it turns slowly around the axis, imparts a slight but continuous axial vibratory motion to the casing 188. This motion is to be continued while the casing is set in cement, as already described in connection with FIGS. 1 to 4, inclusive.

FIG. 15 combines both a rotary and a longitudinal vibratory motion to the casing 180. Corresponding parts in FIGS. 1 and 15 are designated with the same reference characters, and the structure of FIG. 15 differs from that of FIG. 1 in that the bottom surface of the rotary housing 15 is formed with segmental ring-shaped cam surfaces as shown in FIGS. 12 and 14. In this structure a roller cage 2% is interposed between the bottom of the rotary table 15 and the annular base surface 186. When the housing 15 is slowly rotated by the motor 50, the casing will be given not only a slow rotary movement but also an axial vibratory movement, which is caused by the segmental ring cam surfaces 188 on the bottom of the rotary table 15 riding over the rollers 203.

The roller cage 2% is composed of a ring 202 on which a plurality of rollers 203 are rotatably mounted on pins 204. The ring 202 of the roller cage is formed to rest on the annular surface 186 of the base and hold the rollers slightly above and out of contact with that surface.

This arrangement is such that when the rotor 50 is operated and the-rotary table 15 is slowly rotated, it will not only have a slow rotary motoin but will also, by reason of the cam surfaces 188 which contact the rollers 203, have an axial vibratory motion in addition.

While I have shown and described the best embodiments of this invention now known to me, various modifications in these embodiments and other embodiments may be made without departing from the spirit of this inventlon, so that only such limitations may be imposed as are indicated in the appended claims.

I claim:

1. The method of setting a hollow cylindrical metal tube 111 concrete within an earth borehole or the like which consists in supplying cement grout around the exterior of the tube and rotating the tube at a speed not to exceed one revolution per minute while the cement is being introduced into the borehole around the tube, but is not rosated with the tube, and until the cement is completely se 2. The method of providing for the ready removal of the casing of an oil well after it has been cemented in at least one zone, which consists in moving the casing very slowly, at a speed not exceeding one revolution per min ute, in a rotary direction without rotating the cement, while the cement is introduced and until the cement is fully set.

3. The method of producing hollow concrete piles in situ which consists in forming a hole in the earth, inserting a metallic core with a smooth outer surface substantially concentric with the hole in the earth, introducing cement grout into the space between the metallic core and amazes the hole in the earth, and rotating the core at a speed not to exceed one revolution per minute while the cement is being introducedand continuously until it is fully hardened.

4. The method of producing cylindrical or conical concrete blocks which consists in rotating a mould havinga smooth inner surface about its axis in a vertical position at a speed not to exceed one revolution per minute, introducing wet concrete into the mould while it is rotating, without rotating the concrete, continuing the slow rotation of the mould until the concrete is fully hardened, and withdrawing the block from the mould.

5. The method of producing hollow cylindrical or conical concrete blocks which consists in rotatably mounting a hollow mould and an inner core in substantially concentric vertical relation, introducing wet concrete into the mould around the core and rotating both the mould and the core in opposite directions at speeds not to exceed one revolution per minute until the concrete is fully hardened, and withdrawing the core and the mould.

6.. The method of claim-2 in which the casing is slowly oscillated.

7. The method of claim 4 in which the mould is slowly oscillated, the speed of rotary movement being substantially at the rate of one revolution per minute.

8. The method of claim 2 in which the casing is slowly vibrated in a longitudinal direction in addition to the slow rotary movement.

9. The method of claim 4 in which the mould is also vibrated in a longitudinal direction.

'10. The method of 'settingan oil well casing which comprises providing a clutch mechanism for holding the casing against longitudinal movement at will and permitting the casing to be lowered as required and means for rotating the clutch mechanism, introducing cement grout into the casing and forcing it outof the open bottom end of the casing around the exterior surface of the casing between the casing and the earth at any desired location, and rotating the clutch mechanism and the casing at a speed not to exceed one revolution per minute While the cement grout is being introduced and until it has completely set, whereby the casing may be withdrawn when the well is abandoned.

11. The method of producing cylindrical or conical concrete blocks which consists in rotating about its axis a mould set in a vertical position and having a smooth inner surface, introducing cement grout into the mould and rotating the mould at a speed not exceeding one revolution per minute, imparting a slight vibratory axial movement to the mould and continuing said movement while the grout is 'being introduced and until the cement is fully hardened.

12. The method of forming hollow concrete piles that comprises forming a hole in the earth of a depth corresponding to the desired length of the pile, inserting a tapered mandrel in the hole corresponding to the desired hollow in the pile, pouring cement grout-into the hole around the mandrel, continuously rotating the mandrel about its longitudinal axis at a speed of approximately one revolution per minute until the cement is completely set, removing the mandrel and filling the hollow with additional cement grout.

13. The method of forming a concrete oil well lining which consists of placing a metal casing in the hole, filling the space around the casing with cement grout and slowly and continuously rotating the. casing on its longitudinal axis at a speed not to exceedone revolution per minute until the cement is completely set and removing the casing.

References Cited by the Examiner UNITED STATES PATENTS 1,337,618 4/20 Pipe 25-41.3 1,514,980 11/24 Mathis 2541.5 1,593,696 7/26 Hyden et al 264-3l2 XR 1,648,475 11/27 Darwin 264310 XR 1,789,818 l/31 Hyden et al 264-312 1,865,652 7/32 Upson 2511 2,296,018 9/42 Boyle 264312 XR 2,421,666 6/47 Upson etal. 6153.66 2,429,012 10/47 Zigenbein 2 64-312 XR 2,482,949 9/49 Tankovich 25--37 2,845,682 8/58 Eschenbrenner 2537 2,966,714 1/61 Eways et a1. 25-30 3,034,304 5/62 Upson 61--53.52 3,072,965 1/ 63 Miller 264310 XR ROBERT F. WHITE, Priinary Examiner. ALEXANDER H. BRODMERKEL, Examiner. 

1. THE METHOD OF SETTING A HOLLOW CYLINDRICAL METAL TUBE IN CONCRETE WITHIN AN EARTH BOREHOLE OR THE LIKE WHICH CONSISTS IN SUPPLYING CEMENT GROUT AROUND THE EXTERIOR OF THE TUBE AND ROTATING THE TUBE AT A SPEED NOT TO EXCEED ONE REVOLUTION PER MINUTE WHILE THE CEMENT IS BEING INTRODUCED INTO THE BOREHOLE AROUND THE TUBE, BUT IS NOT ROTATED WITH THE TUBE, AND UNTIL THE CEMENT IS COMPLETELY SET. 